N-(aminoakyl)phthalimides

ABSTRACT

NEW ORGANIC COMPOUNDS USEFUL AS ADDITIVES FOR MOTORFUELS ARE OF THE FORMULA   2-(R-(NH-(CH2)N)M-),4-R1,5-R2,6-R3,7-R4-PERHYDROISOINDOLE-   1,3-DIONE   WHEREIN THE HYDROCARBON RING IS A CYCLOHEXANIC, AROMATIC, DIHYDROAROMATIC OR TETRAHYDROAROMATIC RING, R1, R2, R3 AND R4 ARE EACH A HYDROGEN ATOM OR AN ALIPHATIC, LINEAR OR BRANCHED, SATURATED OR UNSATURED HYDROCARBON RADICAL, R1 TO R4 HAVING AS A WGOLE FROM 0 TO 30 CARBON ATOMS, R1 AND R4 BEING OPTIONALLY INTERCONNECTED SO AS TO FROM A BICYCLIC COMPOUND, THE ASSEMBLY-R1-R4 COMPRISING 1 TO 2 CARBON ATOMS, N IS AN INTEGER FROM 2 TO 10, M IS AN INTEGER FROM 0 TO 10 AND R IS A MONOVALENT ALIPHATIC HYDROCARBON RADICAL CONTAINING FROM 1 TO 30 CARBON ATOMS.

United States Patent Office 3,804,852 Patented Apr. 16, 1974 US. Cl. 260-326 C 28 Claims ABSTRACT OF THE DISCLOSURE New organic compounds usefulas additives for motorfuels are of the formula wherein the hydrocarbon ring is a cyclohexanic, aromatic, dihydroaromatic or tetrahydroaromatic ring, R R R and R are each a hydrogen atom or an aliphatic, linear or branched, saturated or unsaturated hydrocarbon radical, R to R4 having as a whole from to 30 carbon atoms, R and R being optionally interconnected so as to form a bicyclic compound, the assembly R R com prising 1 to 2 carbon atoms, n is an integer from 2 to 10, m is an integer from 0 to and R is a monovalent aliphatic hydrocarbon radical containing from 1 to 30 carbon atoms.

This invention relates to new organic compounds, which can be used as additives for motor-fuel compositions.

It is a particular object of the invention to provide new imide compounds as well as the products obtained by neutralization, either partial or total, of said compounds by means of alkylphosphoric acids.

The invention has also as particular object the use of these new compounds and their neutralization products as additives having a detergent, anti-frost and anti-corrosion action in motor-fuel compositions, and particularly in those which are used in spark ignited engines. 1

A further object of the invention is the use of the new imide compounds in association with mineral oils, as additives for motor-fuel compositions, the latter additive compounds exhibiting in addition to the already mentioned detergent, anti-frost and anti-corrosion properties, good cleaning properties. 7

It is a further particular object ofthe invention to provide motor-fuel compositions containing at least one of the above-described additives.

It is known that the use of motor-fuelsof the gasoline type, particularly in motor-cars, is associated wih several carburetion problems. Thus, it is known that the formation, on the different parts of the carburetor, of substantial deposits, responsible for misfirings and stalling's of the motor, occurs frequently in motor-cars, particularly during town traffic and/or by hot weather.

This deposit formation is still increased by the use of devices for the suction of the gases of the crankcase known as Positive Crankcase Ventilation (P.C.V.), used to reduce pollution of the atmosphere. It is known, hesides, that 'under certain hygrometric and temperature conditions, ice crystals appear on the metal walls of the carburetor onto which they adhere. They may accumulate there in a substantial amount such as to obstruct the admission port at the level of the throttle valve of the carburetor. It is known finally, that the water dissolved in the gasoline, may corrode the engine metal parts.

By gasoline it is intended to mean hydrocarbon motorfuels for spark-ignited engines, having a boiling range essentially between 30 and 200 C.

Attempts have been made for reducing these disadvantages by adding different additives to gasoline at generally low concentrations (about 50 parts per million of parts by weight), in order to avoid the formation of deposits in the carburetor (detergent action), to prevent adherence of the ice crystals to the metal walls (anti-frost action) and to form a protective film on the various metal parts of the motor (anti-corrosion action).

For combining these various actions in a single molecule, it has been suggested to use as additives, various organic compounds comprising in their molecule, generally, one or more linear parts soluble in gasolines, as well as one or more polar parts.

There have now been discovered new organic compounds containing nitrogen which, when dissolved in motor-fuels, exhibit improved properties with respect to the detergent, anti-frost and anti-corrosion elfects, as abovementioned, as well as other advantages which will appear from the following description.

' The compounds of the present invention have the following formula:

wherein the hydrocarbon ring may be a cyclohexanic, aromatic, dihydroaromatic or tetrahydroaromatic ring, R R R and R, are selected separately from the group consisting of the hydrogen atom and the linear or branched hydrocarbon radicals, either saturated or not, the number of carbon atoms of R to R taken as a whole, being in the range of from 0 to 30, the radicals R and R being optionally interconnected so as to form a bicyclic compound, the assembly R R then optionally comprising 1 or 2 carbon atoms,'n being an integer having a value from 2 to 10, m being an integer having a value from 0 to 10 and R being a linear or branched aliphatic monovalent hydrocarbon radical, saturated or not, having a number of carbon atoms from 1 to 30.

' When the number of carbon atoms of R is lower than 5, the number of recurring units {(CH NH-} will be preferably high, for example from 5 to 10.

As specific examples of the compounds according to the invention, there can be mentioned those wherein the hydrocarbon ring of the imide portion, substituted or not, the radical R, and the numbers n and m of the amine part are indicated in the table below.

6 R1 R: R: RI R m 1| Cyclohexyl n H H H H 9 octadeeenyl-l (oleyl)... 1 3

D Methyl H e l-l 2 5 Dn Ethyl- H- 1 3 Phenyl nn H H 9 octadeeenyl-1.. 1 3

Do Methyl.. H MethyL- H Dodeeyl-l (lauryl) 5 3 D DodeeyL. H H H Eieosyl-l 1 3 LZ-dlhydtopherwlma H Fl H H 8 3 Do Methyl-.-. H H H 1 3 D0 PropyL. H Oetadecyl-L. 1 4 1,2,3 fi-tetrahydrophenylnnn H H 1 10 b0 Methyl..- H H 1 5 D Butenyl... H H 2 3 3,6 endomethylene cyclohexylona H H H 1 8 3,6end1methy1ene eyclohexyleue H MethyL. MethyL. H 1 4 3,6 endomethylene 1,2,3,6 tetrahydrophenylene.... H- H H 1 3 3,6 endimethylene l,2,3,6 tetrhhydrophenylene..-. H-. Methyl... Methyl- H Octadecyl-l 1 3 The compounds according to the invention may be obtained for instance:

(a) By the reaction of an ortho-dicarboxylic compound of general formula:

R2- COOH wherein the ring may be aromatic, dihydroaromatic, tetrahydroaromatic or cyclohexanic, the substituents R R R and R being defined as above, R being a linear or branched aliphatic radical containing for example from 1 to 12 carbon atoms or a phenyl radical optionally substituted, and the arrows indicating an isomerism possibility, or

(b) By the reaction of an anhydride of an ortho-dicarboxylic acid having the general formula:

the general characteristics of which are defined as above, with at least one aliphatic mono primary amine of the general formula:

The condensation of the dicarboxylic compound on the mono-primary amine(s) will be carried out by the reaction of substantially equimolecular amounts of these compounds either in a dry state, or in a solvent.

There will be used advantageously a solvent capable of forming an azeotrope with the water produced in the reaction. The azeotropic distillation of water will insure the evolution of the reaction towards the formation of the desired imide. Among the solvents which can be used, there will particularly be mentioned benzene, toluene and xylenes as well as their mixtures which have the advantage of being a part of the gasoline composition.

Moreover, it has been observed that the increase of the content of polar groups, obtained by associating the alkylphosphoric acid type compounds to the nitrogen compounds of the Formula 1, results in a substantial increase of the solubility of the additive in the mixtures of aromatic solvents and improves some of the above-mentioned actions, particularly the anti-frost action.

The invention accordingly relates also to the compounds resulting from the neutralization of a compound of the Formula 1, by at least one alkylphosphoric acid, as follows:

wherein R R R R R, n and m have the same meaning as previously, R is an aliphatic linear or branched hydrocarbon radical, the number of carbon atoms of which may vary preferably from 8 to 18, and p and z are integers so selected that the sum of the -OH groups of the acids is at most equal to the number of amine groups present in the nitrogen compound.

Among the alkyl-phosphoric acids which can be used, the mixtures of monoalkyl and dialkyl-phosphoric acids obtained by reacting phosphoric anhydride with'an alcohol or a mixture of aliphatic linear or branched alcohols, are particularly advantageous.

The reaction may be illustrated. as follows:

..o 3R'0H P205 (R'OhPOOH (R0)iE (OH)= wherein R is a linear or branched alkyl radical having preferably a number of carbon atoms of from 8 to 18.

The alcohol to be used may be selected for the purpose of obtaining a motor-fuel composition resistant to water extraction. The use of branched alcohols such as, for instance, ethylhexyl alcohol is, accordingly, preferred.

The neutralization reaction of the imide of the Formula 1 may be achieved by the addition of 'alkyl-phosphoric acid(s) to a solution of said imide in an aromatic solvent, and by maintaining the reaction mixture, for about 1 hour, at a mean temperature of from about to 100 C.

According to the invention, the imides of the'Formula 1, used as such or partially or completely neutralized by alkylphosphoric acids, are added to motor-fuel compositions at concentrations of from 10 to 250, and preferably from 10 to 100 parts per million of parts by weight, and this without turbidity being observed in the motor-fuel, even when the addition is made at a low temperature. These compounds may be associated with the usual additives without disadvantages.

It has been discovered that the imides of the Formula 1, used in a motor-fuel in association with a minor amount of at least one mineral oil, form moreover, additives having a cleaning action. Thus, there is used, for example, from 50 to 2000 p.p.m. by weight of a mineral oil, such as for example, a naphthenic oil and from 10 to 250 p.p.m. by weight of at least One compound of the Formula 1.

The following non-limitative examples, are given for the purpose of further illustrating the invention.

EXAMPLE 1 A mixture of 16.3 g. of N-oleyl propylene diamine (0.05 mole), 7.6 g. of tctrahydro-o.phthalic anhydride (0.05 mole) and 60 ml. of a mixture of toluene and xylene by equal parts by volume, is introduced into a three-neck flask, provided with the device of Dean and Stark and with a thermometer.

An inert gas is bubbled therethrough. The mixture is brought to reflux for several hours until there is recovered by azeotropic distillation about 1 ml. of water. The solution is cooled down and then adjusted to a known volume by means of the same mixture of solvents, so as to obtain a titrated solution of N-(3-oleyl-amino-propyl)tetrahydroo.phthalimide.

EXAMPLE 2 8.8 g. of an equimolecular mixture of monoand dioctylphosphoric acids, which corresponds to 0.05 hydroxyl equivalent, is added to the solution prepared in Example 1. The addition is carried out in such a manner that the temperature of the mixture is maintained below 65 C. The reaction mixture is then brought to about 80 C. for 1 hour under stirring. There is obtained an oily product which is adjusted to a known volume by means of a mixture of toluene and xylene by equal parts by volume, so as to obtain a titrated solution.

EXAMPLE 3 A mixture comprising 7.4 g. of o.phthalic anhydride (0.05 mole), 16.3 g. of N-oleyl propylene diamine (0.05 mole) and 60 ml. of a toluene-xylene mixture by equal volumes, is introduced into the device described in Examle 1. p The solution is brought to reflux until there is recovered about 1 ml. of water. The obtained solution is then adjusted to a known volume by means of a mixture of the preceding solvents so as to obtain a titrated solution of N(3-oleylamino propyl) phthalimide.

6 EXAMPLE 4 8.8 g. of an equimolecular mixture of mono and dioctyl phosphoric acids, corresponding to 0.05 hydroxyl equivalent is added to the solution prepared in Example 3. The addition is carried out under such conditions that the temperature is kept below 65 C. The reaction mixture is then brought to 80 C. for 1 hour under stirring. There is obtained an oily product, which is adjusted to a known volume by means of a toluene-xylene mixture by equal volumes, so as to obtain a titrated solution.

EXAMPLE 5 9,088 kg. of xylene, 7.380 kg. of a mixture having as essential components N-oleyl propanediamine and N- stearyl propanediamine (known under trademark Dinoram-S) are introduced into a reactor of 70 liters, provided with a stirring device and a system for azeotropic entrainment.

There is added 0.1 kg. of 4,4-dihydroxy 3,5,3',5,- tetratertiobutyl diphenylmethane.

The feed is brought to 35-40 C. so as to dissolve the Dinoram-S mixture in xylene. There is then added, stepwise, 2.960 kg. of phthalic anhydride. After the total addition of phthalic anhydride, the reaction mixture is brought to reflux and water is removed by azeotropic entrainment.

After reflux for 2 hours, the reaction is completed.

97% of the theoretical water amount have been removed and there is thus obtained a solution of N-(3- oleyl aminopropyl) phthalimide and N-(3-stearyl aminopropyl) phthalimide. This solution has a viscosity of 6.2 cst. at C. It titrates 48.2 g./100 cc.

The total alkalinity is 0.997 NH equivalent per gram of solution.

EXAMPLE 6 Determination of the carburetor merit There is used a motor of the trademark Renault R16 and of the type 69-701, equipped with a Solex carburetor of the type 35 D.I.T.A.2.

This motor, lubricated with a multigrade 20 W/ 40 commercial oil, is fed with a premium gasoline having the following composition by weight:

Percent Aromatic hydrocarbons 39 Olefins 4 Saturated hydrocarbons 57 and which contains, in addition, 0.5 g./l. of lead.

The motor is run over 48 hours, while 10 to 12% of the exhaust gases are recycled. At each test the consumption of premium gasoline is about 200 liters.

'For each test, there is used a new carburetor (thus of a merit equal to 10).

The carburetor is disassembled at the end of the test and its merit is evaluated.

In the following table, the results of the tests carried out with the above described premium gasoline are summarized:

(1) without detergent additive (2) with 35 ppm. (by weight) of the compound accord- 7 EXAMPLES 7 TO 22 In these examples, there have been also prepared imide compounds having the formula:

wherein the hydrocarbon ring, the substituents R to R the numbers n and m and the radical R are as indicated in the following table.

gen or methyl, R is hydrogen, R is 9-octadeceny1-l, decyl-l or eicosyl-l, m is 1-5, and n is 3.

7. A compound as defined by claim 1 wherein said hydrocarbon ring is 1,2-dihydrophenylene.

8. A compound as defined by claim 7 wherein R is hydrogen, methyl or propyl, R is hydrogen, R is hydrogen or propyl, R is hydrogen, R is hexyl-l, 9-octadecenyl- 1 or octadecyl-l, m is 1-8, and n is 3 or 4.

9. A compound as defined by claim 1 wherein said hydrocarbon ring is 1,2,3,6-tetrahydrophenylene.

10. A compound as defined by claim 9 wherein R is hydrogen, methyl or butenyl, R is hydrogen, R is hydrogen, R is hydrogen or methyl, R is 9-octadecenyl-1, octadecyl-l, or dodecyl-l, m is 1 or 2, and n is 3-10.

Example 6 R1 R2 R1 R; R m n 7 OyeIohexylene.-. H H 9 oetadeeenyl-1(oley1) 1 3 a do H Hex -1 2 5 0 do Ethyl. Octadecyl 1 (stearyl)- 1 3 10 Phenyl H 9 oetadecenyl-l 1 3 11 d la yl 5 3 12 d 1 3 13 1, 2-dihydrophenylene 8 3 14 do Methyl H..- 1 3 15 do 1 4 16 1, 2, 3,6 tetrahydrophenylene H H 1 0 17 do Methyl H 1 5 is do Butenyl.-. H 2 3 19 3,6endomethylene eyelohexylene H H H 9octadecenyl-1- 1 3 20 3,6 endodimethylene eyelohexylene H Methyl.... Methyl H..- Octadecyl-1 1 4 21 3, 6 endomethylene 1, 2,3,6 tetrahydro phenylene.. H.. H H... 9 octadecenyl-l. 1 3 22 do H Methyl...- Methyl. H Oetadecyl-l 1 3 These compounds have been tested in the same manner as in Example 6. The results obtained are similar to those given in this example.

What we claim as this invention is: 1. A compound of the formula:

0 R N-L-(CH) -NH1-R I a B L Jm wherein the hydrocarbon ring is the cyclohexanic, aromatic, dihydroaromatic or tetrahydroaromatic, R R R and R are separately selected from the group consisting of hydrogen and alkyl of 1-12 carbon atoms, the number of carbon atoms of R to R taken as a whole, varying from 0 to 30, the radicals R and R being optionally interconnected so as to form a bicyclic compound, the assembly -R R consisting of 1 to 2 carbon atoms inclusive, n is an integer from 2 to 10, inclusive, m is an integer from 1 to 10 inclusive and R is an alkyl or alkenyl radical having from 1 to 30 carbon atoms inclusive with the provision that the group {-(CH ),,NH} R contains at least 16 carbon atoms.

2. A compound as defined by claim 1 wherein R is less than 5 and m is 5-10.

3. A compound as defined by claim 1 wherein the hydrocarbon ring is cyclohexylene.

4. A compound as defined by claim 3 wherein R is hydrogen, methyl or ethyl, R and R are hydrogen, R is hydrogen or ethyl, R is 9-octadecenyl-1, hexyl-l or octadecyl-l, m is 1 or 2, and n is 3-5.

5. A compound as defined by claim 1 wherein said hydrocarbon ring is phenylene.

6. A compound as defined by claim 5 wherein R is hydrogen, methyl or dodecyl, R is hydrogen, R is hydro- 75 11. A compound as defined by claim 1 wherein the hydrocarbon ring is 3,6 endomethylene cyclohexylene.

12. A compound as defined by claim 11 wherein R and R are hydrogen, R and R are hydrogen or methyl, R is 9-octadecenyl-l or octadecyl-l, m is l and n is 3 or 4.

13. A compound as defined by claim 1 wherein said hydrocarbon ring is 3,6 endomethylene-l,2,3,6 tetrahydrophenylene.

14. A compound as defined by claim 13 wherein R and R are hydrogen, \R, and R are hydrogen or methyl, R is 9-octadecenyl-1 or octadecyl-l, m is 1 and n is 3.

15. A compound as defined by claim 1 wherein said compound is N(3 oleyl amino propyl)tetrahydroo.phthalimide.

16. A compound as defined by claim 1 wherein said compound is N(3-oleylamino propyl)phthalimide.

17. A compound as defined by claim 1 wherein said compound is N-(3-stearyl amino-propyl)phthalimide.

18. A compound as defined by claim 1 wherein n is 3.

19. A compound as defined by claim 1 wherein 'R R R and R are all hydrogen.

20. A compound as defined by claim 18 wherein R R R and R are all hydrogen.

21. A compound as defined by claim 18 wherein R is octadecenyl-l.

22. A compound as defined by claim 19 wherein R is octadecenyl-l.

23. A compound as defined by claim 3 wherein R R R and R are all hydrogen, R is 9-octadecenyl-1, m is 1, and n is 3.

24. A compound as defined by claim 7 wherein R R R and R are all hydrogen, R is hexyl, m is 8 and n is 3.

25. A compound as defined by claim 9 wherein R R R and R are all hydrogen, R is 9-octadecenyl-l, m is 1 and n is 10.

26. A compound as defined by claim 11 wherein R R R and R are all hydrogen, R is 9-octadecenyl-1, m is 1 and n is 3.

9 v 10 27. A compound as defined by claim 13 wherein R OTHER REFERENCES R :R and R are all hydrogen, R is 9-octadecenyl-1, m

is1andnis3. 4

28. A compound as defined by claim 1 dissolved in a Chem 2 11 1 2 (1959) solvent selected from the group consisting of benzene, 5 JQSEPH NARCAVAGE, Primary Examiner toluene or xylene.

References Cited US. Cl. X.R.

UNITED STATES PATENTS 260-326 E, 326 N; 4463 2,698,850 1/1955 Long et al. 260--326 3,025,300 3/1962 Huebner 260326 X 10 Yanagi: Chem. Abs., vol. 54:5425 (1960), Abs. of J. 

